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HomeMy WebLinkAboutPre-Design Workshop Meeting #1.pdfCity of Renton Well 5A Water Treatment Improvements – Pre-design Workshop Meeting #1 - December 21, 2006 Agenda Attendees: Introductions 1. Workshop Objectives • Identify and agree on key project requirements • Review permits & approvals needed • Review selected treatment process and features • Identify and discuss site layout and building options 2. Key Project Requirements • Treatment requirements • Operations • Overall project schedule • Integration with surrounding community 3. Permits and Project Approvals Needed • Conditional Use permit • SEPA • Stormwater discharge • NPDES process waste discharge permit • DOH approval of Pre-design (Project) Report • Pre-application meeting with City Development Services - timing 4. Treatment Process • Same as Maplewood (air eductor, GAC, chlorine injection, greensand, breakpoint chlorination contacting, fluoride, polyphosphate) • Approximate sizes of unit processes • Chlorination method – commercial or on-site hypochlorite • General control and telemetry requirements • Process operations water discharges o Pump-to-waste water o Treated water from startup prior to introduction to distribution system o Backwash water basin overflows 5. Site Layout and Building Options • Impacts to adjacent properties o Screening o Setback requirements o Limits of vertical development o Noise control • Retain existing wellhouse o Advantages / drawbacks • Remove existing wellhouse o Advantages / drawbacks • Process vessels o Completely enclosed in building o Open bay • Below-grade basins o Completely under building o Partially under building • Electrical o power supply to site may impact layout and building options o emergency generator 6. Instrumentation & Controls • Set meeting with City and Reid Instruments to determine hardware and software options 7. Summary of Key Decisions and Next Steps • Decisions Made during Workshop #1 • Decisions to be Made – Needs and Timing • Pre-design Workshop #2 o Topics o Target date to meet City of Renton Well 5A Water Treatment Improvements – Pre-design Workshop Meeting #1 - December 21, 2006 Topics Discussed and Key Notes and Decisions Attendees: City of Renton: K/J: HDR: Reid Instruments: JD Wilson Milt Larsen Greg Pierson Tom Reid Ray Sled Chris Kelsey Randy Geist Dan Scottie Ernie Swanson Lys Hornsby Jeff Hauck Abdoul Gafour 1. Workshop Objectives • Identify and agree on key project requirements • Review permits & approvals needed • Review selected treatment process and features • Identify and discuss site layout and building options 2. Key Project Requirements • Treatment requirements • Operations No well operations needed during construction. • Overall project schedule Design in 2007; construct in 2008; on-line NLT summer 2009 • Integration with surrounding community 3. Permits and Project Approvals Needed • Conditional Use permit • SEPA • Stormwater discharge • NPDES process waste discharge permit • DOH approval of Pre-design (Project) Report • Pre-application meeting with City Development Services Plan on meeting on Jan. 11/12 to better identify permit and zoning setback requirements. Will likely need a stream study – timing to be determined. • Applicable design codes: IBC 2006; NEC 2005. 4. Treatment Process • Same as Maplewood (air eductor, GAC, chlorine injection, greensand, breakpoint chlorination contacting, fluoride, polyphosphate) • Approximate sizes of unit processes Unit processes sized for full well production rate of 1500 gpm. • Per City, backwashing of vessels does not need to be done while well is on-line. Therefore, number and sizes of vessels will be designed for total production rate of 1500 gpm only. • Assumption is that backwash water supply can be from the local distribution grid, but needs to be checked. HDR to provide City with backwash flow rates and durations. City to run hydraulic model to determine potential impacts on pressures in local grid during backwashing. • Chlorination method – commercial or on-site hypochlorite Prepare comparison tech memo, as per scope. • General control and telemetry requirements Same as existing water facilities. Include telephone land lines. City has wireless network – may consider utilizing this for telecomm. • Process operations water discharges o Pump-to-waste water o Treated water from startup prior to introduction to distribution system o Backwash water basin overflows o Provide capability to pump the chlorine contact basin out to sewer and/or backwash basin. o May need to upgrade local sewer lines to accept additional flows from new facility. 5. Site Layout and Building Options • Impacts to adjacent properties o Screening o Setback requirements o Limits of vertical development o Noise control • Option to remove existing wellhouse was discussed o Possible advantages: more space on site for optimal location of structures; fewer buildings; easier to meet access and code setback requirements. o Possible drawbacks: negative perceptions of removing a relatively new building, o HDR-K/J to develop conceptual alternatives with and without existing wellhouse and relative estimated cost differences. City will then make a decision on the whether or not the existing wellhouse can be removed. • Location of process vessels o Completely enclosed in building (similar to Maplewood) o Open bay Possible advantages: Easier media loading; no HVAC; lower building costs. Possible drawbacks: screening; security (If vessels are in open bay(s), will need screening walls on all sides for security.) • Below-grade basins o Completely under building Provides for least possible total footprint on site. o Partially under building Increases total footprint. Will need a portion of the CCB and BW basins under the pump room of the treatment building (finished water booster pumps and backwash handling pumps). • Electrical o power supply to site may impact layout and building options o emergency generator City has determined that the generator will be trailer mounted with sound attenuation, diesel, auto-start and auto-transfer, auto-testing, housed in garage or in bay of a building (i.e., protected from weather and lighted) at the Well 5A site; the amount of on-trailer fuel storage and on-site fuel storage to be determined (need recommendation from consultant). Preliminary estimate of size is 400 – 500 kW. 6. Instrumentation & Controls • Set meeting with City and Reid Instruments to determine hardware and software options Prior to this meeting, consultant to determine if process equipment vendors can provide viable PLCs for their respective systems. This will drive the type and extent of I&C programming needed. Plan on meeting in early February. 7. Pre-design Workshop #2 o Topics As per the scope of work. o Target date to meet Plan on mid-February. MEMORANDUM Draft for review only – 1/19/07 To: J.D. Wilson, Renton Water Utility From: Greg Pierson, HDR cc: Milt Larsen, K/J Date: January 23, 2007 Subject: Considerations for Removal or Retention of the Existing Well 5A Building The purpose of this memo is to outline some key considerations to assist with the City’s decision as to whether to remove or retain the existing well building at Well 5A as part of the water treatment improvements project. Attached are two conceptual site sketches of the well site to help illustrate the points made in this memo. Figure 1 shows a possible site layout with the new treatment building and the existing well building, while Figure 2 shows a possible site layout with the well building removed. The size and configuration of the new treatment building is approximate based on preliminary facility sizing requirements and is not intended to represent our recommended configuration at this time, however I believe that the overall footprint size of this building will be fairly close to that shown in the figures. The key considerations are outlined in the table below and the relative advantages and drawbacks for each are noted in terms of removing the existing building. Key Consideration Advantages (existing building removal) Drawbacks (existing building removal) Space for new facilities - Allows for more optimal location of new facilities for access - Easier to meet permitted setback requirements from parcel boundaries and stream - None Space for construction of new facilities - More space for below- grade excavations - More space for laydown areas and construction equipment - None Aesthetic impacts - One new building has would have a “cleaner”, more integrated look with - Possible negative perception for City to remove the existing less visual impact to the surrounding neighborhood - No need to match architecture of new building to the existing building, esp. roof type building Protection of the existing building during construction - Would preclude protecting the existing building during construction - Will need to protect the wellhead during building demolition Functional / operational integration with existing building - All treatment and pumping operations would be in one building - Existing well head, pump, and control valves would be incorporated into new building - Precludes potential design issues for integrating the existing building with the new building, esp. electrical and controls - None Impacts on size of the new treatment building - Relatively little increase in new building size to include the well pump and controls and a lavatory – estimate not more than about 200 sf additional needed out a total of about 5000 sf (~ 4% more) - Costs for demolition of existing building and the additional new building size to accommodate the well and a lavatory Based on these considerations, there appears to be more advantages to the City by removing the existing Well 5A building than to retain it as part of the new treatment facilities.